Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide and characterized by emphysema, small airway remodeling and mucus hypersecretion. Citrus peels have been widely used as food spices and in traditional Chinese medicine for chronic lung disease. Given that citrus peels are known for containing antioxidants and anti-inflammatory compounds, we hypothesize that citrus peel intake can suppress oxidative stress and inflammatory response to air pollution exposure, thereby alleviating COPD-like pathologies. This study aimed to investigate the efficacy of citrus peel extract, namely Guang Chenpi (GC), in preventing the development of COPD induced by diesel exhaust particles (DEPs) and its potential mechanism. DEP-induced COPD-like lung pathologies, inflammatory responses and oxidative stress with or without GC treatment were examined in vivo and in vitro. Our in vivo study showed that GC was effective in decreasing inflammatory cell counts and inflammatory mediator (IL-17A and TNF-α) concentrations in bronchoalveolar lavage fluid (BALF). Pretreatment with GC extract also significantly decreased oxidative stress in the serum and lung tissue of DEP-induced COPD rats. Furthermore, GC pretreatment effectively reduced goblet cell hyperplasia (PAS positive cells) and fibrosis of the small airways, decreased macrophage infiltration as well as carbon loading in the peripheral lungs, and facilitated the resolution of emphysema and small airway remodeling in DEP-induced COPD rats. An in vitro free radical scavenging assay revealed robust antioxidant potential of GC in scavenging DPPH free radicals. Moreover, GC demonstrated potent capacities in reducing ROS production and enhancing SOD activity in BEAS-2B cells stimulated by DEPs. GC treatment significantly attenuated the increased level of IL-8 and MUC5AC from DEP-treated BEAS-2B cells. Mechanistically, GC treatment upregulated the protein level of Nrf-2 and could function via MAPK/NF-κB signaling pathways by suppressing the phosphorylation of p38, JNK and p65. Citrus peel extract is effective in decreasing oxidative stress and inflammatory responses of the peripheral lungs to DEP exposure. These protective effects further contributed to the resolution of COPD-like pathologies.

Purpose: Synthesis and characterization of silver (Ag)/titanium dioxide (TiO₂) nanocomposite (ATA) to investigate its antiviral activity against the H1N1 influenza virus and antiviral mechanisms. Materials and Methods: A water-dispersible ATA was prepared by a photocatalytic reduction process from AgNO₃ and TiO₂. The characterization of ATA was performed by ultraviolet-visible spectroscopy, X-ray diffraction, high-resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy. The antiviral activities and the antiviral mechanism of ATA were investigated in detail by light microscopy, transmission electron microscopy and biological techniques such as cell cytotoxicity, 50% tissue culture infectious dose detection, western blot and reverse transcription-polymerase chain reaction. Results: These results showed the successful synthesis of ATA nanocomposite with uniform particle size and distribution. It demonstrated the highly efficient antiviral activity of ATA in a dose- and time-dependent manner, as indicated by the reduction of viral titer and the reduction of cytopathic effects caused by viral infection. In the presence of ATA, the structure of the H1N1 influenza virus is directly destroyed and even disintegrated, with the damaged surface membrane proteins and fuzzy contour. It reduces the infection efficiency of influenza by suppressing the activity and expression of hemagglutinin and neuraminidase. The results of mechanistic studies suggested that ATA nanocomposite primarily interferes with virus attachment to viral receptors on the cell surface. Conclusion: Our study suggests that ATA may be a good antiviral candidate against the influenza virus. Compared with AgNPs alone, our synthesized ATA nanocomposites can achieve similar viral inactivation rates using only a much smaller concentration of AgNPs, greatly reducing the amount of AgNPs and their potential side effects. It has great practical value for attaching ATA to the high-efficiency particulate air network in the air purifier, which can kill the virus attached to it and limit its spread.

Ambrosia artemisiifolia (Amb a) contains many allergens. Allergic conjunctivitis caused by Ambrosia artemisiifolia and its related allergen-specific immunotherapy (AIT) are seldom studied at present. poly(DL-lactide-co-glycolide)-polyethylene glycol (PLGA-PEG) is a very good nano-carrier, which has been applied in the medical field. In this context, we studied the immunotherapy effect and potential mechanism of recombinant Amb a 1 (rAmb a 1)-loaded PLGA-PEG nanoparticles. A mouse allergic conjunctivitis model was established with Ambrosia artemisiifolia crude extract, and the nanoparticles were used for AIT through direct observation of conjunctival tissue, degranulation of mast cells in conjunctival tissue, serum-specific antibodies, cytokines and other assessment models. The treatment of nanoparticles enhanced the secretion of T-helper 1 (Th1) cytokine Interferon-gama (IFN-γ) and the production of immunoglobulin G (IgG)2a (IgG2a), inhibited the secretion of T-helper 2 (Th2) cytokine Interleukin (IL)-13 and IL-4 and the level of IgE. Especially, degranulation of mast cells and expression of mast cell protease-1 (MCP-1) in conjunctival tissue was reduced significantly. In this study, we proved that the nanoparticles prepared by rAmb a 1 and PLGA-PEG have an immunotherapy effect on allergic conjunctivitis in mice.

As bacterial endosymbionts, Cardinium typically undergoes genome reduction, but the molecular process is still unclear, such as how plasmids get involved in chromosome reduction. Here, we de novo assembled 2 genomes of Cardinium in astigmatic mites, especially the chromosome of Cardinium sp.